Molecular sieve materials, both natural and synthetic, have been demonstrated in the past to be useful as adsorbents and to have catalytic properties for various types of hydrocarbon conversion reactions. Certain molecular sieves, such as zeolites, silicoaluminophosphates, aluminophosphates, and mesoporous materials, are ordered, porous crystalline materials having a definite crystalline structure as determined by X-ray diffraction. Within a crystalline molecular sieve material there are cavities which may be interconnected by channels or pores. These cavities and pores are uniform in size within a specific molecular sieve material. Because the dimensions of these pores are such as to accept for adsorption molecules of certain dimensions while rejecting those of larger dimensions, these materials have come to be known as “molecular sieves” and are utilized in a variety of industrial processes.
B. W. Boal et al. (Chem. Mater. 2016, 28, 2158-2164) and J. H. Kang et al. (Chem. Mater. 2016, 28, 6250-6259) disclose germanosilicate molecular sieve CIT-13 and its synthesis using a family of monoquaternary benzyl-imidazolium organic structure directing agents. CIT-13 has a two-dimensional pore system possessing intersecting 14- and 10-membered ring pores.
For catalytic applications, incorporation of catalytic active sites, such as aluminum atoms, is important to impart acidic properties to a molecular sieve.
Accordingly, it has now been found that molecular sieve CIT-13 with aluminum incorporated into the molecular sieve framework structure can be directly synthesized from aluminosilicate FAU framework type zeolites.